For about one third of the year, the ground in about one fourth of the United States is frozen to where it is difficult to dig a large horizontal grave site and extremely difficult to inter a screw-in, self digging or other non-horizontal burial container needing a small cross section space. The earth or ground displacement equipment commonly used to break through the upper layer of frozen soil for a large horizontal grave site experiences trouble in digging a small cross section hole for a vertical coffin interment. Most cemeteries in these colder areas have heavy enough equipment to break up the frozen ground and dig the large, usually four feet wide by seven feet deep by seven to eight feet long hole required for a horizontal burial. Naturally, this increases the already higher costs of horizontal burial over vertical burial.
Screw-in coffins are tapered from the head end to the foot end and have screw threads spiraling around the hull. They are set vertically against the ground, sometimes in a pilot hole, rotated and literally screw into the ground. Self digging and self boring coffins which have cutting elements on their lower edges, are set against the ground and rotated to cut into the ground. These types require about a three foot diameter space in softer less frozen ground. Even with a fairly large pilot hole a screw-in coffin must be rotated back and forth to work it through frozen ground. Once a person has passed away, friends and relatives want them interred as soon as possible. Such action is usually needed to provide closure to those friends and relatives. If the friends and relatives have elected to inter the deceased in a much more environmentally friendly and economical space saving way, a screw-in or self digging coffin is needed.
In winter-frozen ground areas the present invention is the simplest and easiest way to prepare the ground for such an interment. With this invention, the frozen ground is both thawed and softened, making a screw-in, self boring or self digging coffin interment ideal.